Arm apparatus for mounting electronic devices

ABSTRACT

An extension arm suitable for mounting a flat-screen electronic peripheral device, including a forearm extension having at one end a first coupling for attachment to a tilter, a platform or other means for supporting a flat-screen device and at the other end a second coupling. The extension arm also includes a pair of end caps, each having a shaft. The shaft of the first end cap is pivotably rotatable in a support mount, such as a wall, desk or pole mount. The shaft of the second end cap is pivotably rotatable in the second coupling of the forearm extension. The extension arm also includes an upper channel and a lower channel. Each channel has at opposite ends a pair of integrally cast rollers which are pivotably attached to each of the end caps. The upper and lower channels and the end caps form an adjustable parallelogram.

REFERENCE TO CROSS-RELATED APPLICATIONS

The present application is a continuation application which claims thebenefit of the filing date of United States Divisional patentapplication Ser. No. 10/305,568, filed Nov. 27, 2002, which is adivisional of U.S. patent application Ser. No. 10/166,419, filed Jun.10, 2002, which is a continuation of application Ser. No. 09/405,628,filed Sep. 24, 1999, now U.S. Pat. No. 6,478,274, which claims thebenefit of the filing date of U.S. Patent Application No. 60/133,378,filed on May 10, 1999, all of which are entitled “Arm Apparatus forMounting Electronic Devices”, the disclosures of which are incorporatedherein by reference.

BACKGROUND OF THE INVENTION

This invention relates to an arm apparatus for mounting electronicdevices and a method for manufacturing the arm apparatus, and morespecifically to an extension arm suitable to mount a flat-screenedelectronic peripheral device, such as a computer monitor or televisionand the method for manufacturing the extension arm.

Adjustable extension arms for mounting electronic peripheral devices,such as a computer monitor or a television, are well known in the priorart. However, due to recent advances in flat-screen technology, there isa demand for adjustable extension arms that are particularly suited foruse with flat-screen devices, such as flat screen computer monitors andtelevisions.

FIGS. 1-7 are assembly drawings of an extension arm 10 for mounting aperipheral device, in accordance with the prior art. As shown in FIG. 1,the main elements of the extension arm 10 are a first end cap 12, anupper channel 14, a lower channel 16, a second end cap 18, and a forearmextension 20. The first end cap 12 has an end cap shaft 22 that ispivotably attachable to a rigid support mount (not shown), such as anorifice sized to accept the end cap shaft 22 or a track configured andsized to engage the grooves on end cap shaft 22. The first end cap 12 ispivotably coupled via pins 24 to both the upper channel 14 and the lowerchannel 16. The opposite ends of the upper channel 14 and the lowerchannel 16 are pivotably coupled via pins 24 to the second end cap 18.The second end cap 18 is coupled to the forearm extension 20 via aforearm extension pin 92. The forearm extension 20 has a verticallydisposed hole 26 therethrough for accepting a device mount (not shown)such as a tilter, platform or other apparatus. The combination of theupper and the lower channels 14, 16 and the first and the second endcaps 12, 18 form an adjustable parallelogram that permits a devicecoupled to the forearm extension 20 to be raised and lowered to adesirable height. The parallelogram retains its position by employing agas spring 28, which is pivotably and adjustably attached to the firstend cap 12 and the upper channel 14, as will be further described below.Generally, the gas spring 28 is sized so as to have a fixed length untilan upward or downward force is exerted at the second end cap 18 thatexceeds the gas spring's designed resistance. Thus, the gas spring 28causes the parallelogram to retain its position when the only forceexerted at the second end cap 18 is the weight of the device, butpermits the parallelogram to be adjusted when a user pushes the devicecoupled to the forearm extension 20 up or down.

FIG. 2 illustrates a side view of the first end cap 12, having the endcap shaft 22 disposed on a first end 30 of the first end cap 12. Toprovide a rigid connection between the two pieces, the end cap shaft 22is typically machined from steel and is inserted into the first end 30during the casting process of the first end cap 12. The end cap shaft 22has a hole 32 formed in an end of the end cap shaft 22 that is insertedinto the first end cap 12. The first end cap 12 is typically fabricatedfrom cast aluminum. The first end cap 12 also has a second end 34 havinga hole 36 disposed therethrough. Disposed within the first end cap 12 isa threaded rod 38. A first end 40 of the threaded rod 38 is insertedinto the hole 32 at the base of the end cap shaft 22. A second end 42 ofthe threaded rod 38 is aligned with the hole 36 and is held in place bya clip 44. The clip 44 is fastened to an inner surface of the first endcap 12 by screws 46.

Threadedly mounted on the threaded rod 38 is a clevis 48. FIG. 3illustrates a sideview of the clevis 48 including a tapped hole 50 inthe center thereof. The tapped hole 50 receives the threaded rod 38, asshown in FIG. 2. At a first end of the clevis 48 is a pair of fasteningmembers 52, 54 to which are fastened one end of the gas spring 28. Asecond end 56 of the clevis 48 is configured to slidably engage a track58 which is integrally molded in the first end cap 12 (see FIG. 2). Thesecond end 42 of the threaded rod 38 is configured to be engaged by ahex-shaped key which is inserted through the hole 36 when the second end42 is properly aligned with the hole 36. The hex-shaped key is employedso as to rotate the threaded rod 38 along its axis of rotation. When thethreaded rod 38 is rotated along its axis of rotation, the clevis 48moves along the length of the threaded rod 38 in a direction thatcorresponds to the direction which the hex-shaped key is turned. Thismovement of the clevis 48 permits the gas spring 28 to be adjusted.

FIGS. 4(a) and 4(b) illustrate the upper channel 14, which compriseschannel bottom 60 from which extend two channel sidewalls 62. Channelbottom 60 and sidewalls 62 are typically stamped from 13 gauge steelsheet in order to give the upper channel 14 a desired degree ofstructural rigidity. At each of the ends of the channel bottom 60, asemi-circular region 64 of the sidewalls 62 is cut out to accommodatecold-rolled steel rollers 66, which have a hole 68 therethrough forreceiving the pins 24. The rollers 66 are rigidly attached to the upperchannel 14 by MIG welding along the edge of the semi-circular cut outregion 64 and along the ends of the channel bottom 60.

Additionally, the upper channel 14 comprises stiffener 70, which iswelded to an inner surface of the channel bottom 60. Besides providingadditional structural rigidity to the upper channel 14, the stiffener 70has a hole disposed at one end with a threaded ball stud 72 placedwithin the hole and fixed in place by a nut 74. The ball stud 72 isconfigured and sized to receive one end of the gas spring 28. Thelongitudinal centerline 76 of the upper channel 14 is illustrated inFIG. 4(b).

FIGS. 5(a) and 5(b) illustrate the lower channel 16 which comprises achannel bottom 78 from which extend two channel sidewalls 80. As withthe upper channel 14, the channel bottom 78 and sidewalls 80 aretypically stamped from 13 gauge steel sheet, which is relatively heavyin order to give the lower channel 16 a desired degree of structuralrigidity. At opposite ends of the channel bottom 78, a semi-circularregion 82 of the sidewalls 80 is cut out to accommodate cold-rolledsteel rollers 84, which have a hole 86 therethrough for receiving thepins 24. The rollers 84 are rigidly attached to the lower channel 16 byMIG welding along the edge of the semi-circular cut out region 82 andalong the ends of the channel bottom 78. The longitudinal centerline 88of the lower channel 16 is illustrated on FIG. 5(b)

FIG. 6 illustrates the second end cap 18. Unlike the first end cap 12,the second end cap 18 does not have an end cap shaft, nor does it have aclevis assembly for attachment to the gas spring 28. Instead, the secondend cap 18 has a hole 90 disposed in a bottom end for receiving theforearm extension pin 92, and a hole 94 in a side for inserting a pin 96into the forearm extension pin 92, as illustrated in FIG. 1.

FIG. 7 illustrates the forearm extension 20 having the forearm extensionpin 92 welded thereto. The forearm extension pin 92 has a hole 98 formedin an upper end to receive the pin 96. The forearm extension 20 isconfigured to be pivoted around the forearm extension pin 92, and isheld in place within the second end cap 18 by the pin 96 whichpenetrates the hole 94 of the second end cap 18 and the hole 98 of theforearm extension pin 92.

Extension arms 10 of the prior art, such as the one shown in FIGS. 1-7and others like it, are ill-suited for flat-screen monitors andtelevisions, in that they are bulky and cumbersome. In addition, due tothe configuration of its various parts, extension arms 10 of the priorart cannot be flattened against a mounting surface so that the entireextension arm 10 is hidden behind the flat screen device when the deviceis substantially flush with the mounting surface. Additionally, theextension arms 10 of the prior art are costly to manufacture anddifficult to assemble.

Thus, there is a need for an extension arm suitable to mount aflat-screened electronic peripheral device, such as a computer monitoror television, that is inexpensive and easy to manufacture and assemble,and that permits a flat-screen device to be mounted substantially flushwith the mounting surface.

SUMMARY OF THE INVENTION

The present invention, in accordance with one embodiment, relates to anextension arm suitable for mounting a flat-screened electronicperipheral device, such as a computer monitor or television. Theextension arm is inexpensive and easy to manufacture and assemble, andpermits a flat-screen device to be mounted substantially flush with amounting surface.

According to one embodiment, the extension arm comprises a forearmextension that has at one end a first coupling for attachment to atilter, a platform or other means for supporting a flat-screen device.At the other end of the forearm extension is a second coupling. Theextension arm also comprises a pair of end caps each having an end capshaft. The end cap shaft of the first end cap is pivotably rotatable ina support mount, such as a wall, desk or pole mount. The end cap shaftof the second end cap is pivotable rotatable in the second coupling ofthe forearm extension.

The extension arm also comprises an upper channel and a lower channel.The upper channel has at opposite ends a pair of integrally castrollers. Each roller is pivotably attached to each of the end caps. Thelower channel also has at opposite ends a pair of integrally castrollers, which are pivotably attached to each end cap. The upper andlower channels and the end caps form an adjustable parallelogram. Theshape of the parallelogram is retained by a gas spring. One end of thegas spring is attached to a ball stud mounted in the upper channel. Theother end of the gas spring is adjustably mounted to the first end cap.

The extension arm also comprises a clevis, which is located within thefirst end cap. The clevis is pivotably attached to the end of the gasspring which is mounted in the first end cap. A threaded rod threadedlyengages the clevis, such that the clevis slides within the first end capwhen the rod rotates around its axial centerline. The threaded rod isrotatably secured within the first end cap by a retainer clip and a pairof screws.

In one embodiment of the present invention, an upper channel for use inan extension arm that adjustably mounts a device to a support mount, theupper channel comprising a U-shaped body having first and second ends,the body including a pair of spaced apart sidewalls and a bottom wall, afirst roller at a first end of the body and a second roller at a secondend of the body, the first roller including a pair of spaced apartroller walls extending between the sidewalls from the bottom wall, theheight of the roller walls from the bottom wall being less than theheight of another portion of the first roller from the bottom wall.

In another embodiment of the present invention, a lower channel for usein an extension arm that adjustably mounts a device to a support mount,the lower channel comprising a U-shaped body having first and secondends, the body including a pair of spaced apart sidewalls and a bottomwall, a first roller at a first end of the body and a second roller at asecond end of the body, the first roller including a pair of spacedapart roller walls extending between the sidewalls from the bottom wall,the height of the roller walls from the bottom wall being less than theheight of the remaining portion of the first roller from the bottomwall.

In another embodiment of the present invention, the combination of anupper channel and a lower channel for use in an extension arm thatadjustably mounts a device to a supporting mount, the combinationcomprising an upper channel including a U-shaped upper body having firstand second ends, the upper body including a pair of spaced apartsidewalls and a bottom wall, a first roller at a first end of the upperbody and a second roller at a second end of the upper body, the firstroller including a pair of spaced apart roller walls extending betweenthe sidewalls from the bottom wall, the height of the roller walls fromthe bottom wall being less than the height of the remaining portion ofthe first roller from the bottom wall; and a lower channel including aU-shaped lower body having first and second ends, the lower bodyincluding a pair of spaced apart sidewalls and a bottom wall, a thirdroller at a first end of the lower body and a fourth roller at a secondend of the body, the third roller including a pair of spaced apartroller walls extending between the sidewalls from the bottom wall, theheight of the roller walls from the bottom wall being less to the heightof the remaining portion of the third roller from the bottom wall,wherein the upper and lower body and the respective rollers areintegrally cast.

BRIEF DESCRIPTION OF THE DRAWINGS

The subject matter regarded as the invention is particularly pointed outand distinctly claimed in the concluding portion of the specification.The invention, however, both as to organization and method of operation,together with features, objects, and advantages thereof may best beunderstood by reference to the following detailed description when readwith the accompanying drawings in which:

FIG. 1 is an assembly drawing of an extension arm for mounting acomputer monitor, in accordance with the prior art;

FIG. 2 illustrates a first end cap of an extension arm, in accordancewith the prior art;

FIG. 3 illustrates the clevis assembly of an extension arm, inaccordance with the prior art;

FIGS. 4(a) and 4(b) illustrate the upper channel of an extension arm, inaccordance with the prior art;

FIGS. 5(a) and 5(b) illustrate the lower channel of an extension arm, inaccordance with the prior art;

FIG. 6 illustrates a second end cap of an extension arm, in accordancewith the prior art;

FIG. 7 illustrates a forearm extension of an extension arm, inaccordance with the prior art;

FIG. 8 is an exploded assembly drawing of an extension arm foradjustably mounting a flat-screen device to a support mount, accordingto one embodiment of the invention;

FIGS. 9(a)-(d) show several views of end caps, in accordance with oneembodiment of the invention;

FIGS. 10(a)-(d) illustrate several views of an upper channel, accordingto one embodiment of the invention;

FIGS. 11(a)-(e) illustrate several views of a lower channel, accordingto one embodiment of the invention;

FIGS. 12(a) and 12(b) illustrate a forearm extension, in accordance withone embodiment of the invention; and

FIGS. 13(a) and 13(b) illustrate a forearm extension, in accordance withone embodiment of the invention.

DETAILED DESCRIPTION

The present invention, in accordance with one embodiment, relates to anextension arm suitable for mounting a flat-screen electronic peripheraldevice, such as a computer monitor or television, and the method ofmanufacturing the extension arm. FIG. 8 is an exploded assembly drawingof the extension arm, for adjustably mounting a device to a supportmount, according to one embodiment of the invention.

In the embodiment shown, the extension arm 100 comprises a first end cap102, an upper channel 104, a lower channel 106, a second end cap 108,and a forearm extension 110. The first end cap 102 and the second endcap 108 both include a partially enclosed housing 112 and a shaft 114.The partially enclosed housing 112 of both the first and the second endcaps 102, 108 is configured with, for example, holes 116 to receive aconnection mechanism, such as a pin 118, therethrough. The shaft 114 ofthe first end cap 102 is configured to be inserted for pivotablerotation in a support mount (not shown), which may be a wall, a desk, apole mount, or a configurable mount as shown and described inApplicant's co-pending patent applications: application No. 60/106,729filed on Nov. 2, 1998 and application No. 60/108,469 filed on Nov. 14,1998. The shaft 114 of the second end cap 108 is configured to beinserted for pivotable rotation in the forearm extension 110.

The partially enclosed housing 112 of the first end cap 102 alsoincludes a clevis 120, which is pivotably attached to an end of a gasspring 122, mounted therein. A threaded rod 124 is in threadedengagement with the clevis 120, such that the clevis 120 is configuredto slide within the first end cap 102 when the threaded rod 124 rotateson its axis. The threaded rod 124 is rotatably secured in the first endcap 102 by a retainer clip 126 that is attached to the first end cap 102with, for example, screws 128.

The upper channel 104 includes a U-shaped body 130 and integrally castrollers 132 disposed at opposite ends of the U-shaped body 130. Each ofthe rollers 132 is configured to be pivotably attached to a respectiveone of the first end cap 102 and the second end cap 108 with, forexample, the pins 118. The lower channel 106 also includes a U-shapedbody 134 and integrally cast rollers 136 disposed at opposite ends ofthe U-shaped body 134. Each of the rollers 136 is configured to bepivotably attached to a respective one of the first end cap 102 and thesecond end cap 108 with, for example, the pins 118.

The upper and the lower channels 104, 106 and the first and the secondend caps 102, 108 are configured so as to form an adjustableparallelogram. When configured, the shaft 114 of the first end cap 102and the shaft 114 of the second end cap 108 point in oppositedirections. For example, the shaft 114 of the first end cap 102 extendsvertically downward while the shaft 114 of the second end cap 108extends vertically upward. The shape of the parallelogram is retained bythe gas spring 122. One end of the gas spring 122 is attached to a ballstud 138 which is mounted to the upper channel 104. The other end of thegas spring 122 is adjustably mounted to the clevis 120 within the firstend cap 102. Generally, the gas spring 122 is sized so as to have afixed length until an upward or downward force is exerted at the secondend cap 108 that exceeds the gas spring's designed resistance. Thus, thegas spring 122 retains the parallelogram shape when the only forceexerted at the second end cap 108 is the weight of the flat-screendevice. However, the gas spring 122 permits the parallelogram shape tobe adjusted when a user pushes the flat-screen device coupled to theforearm extension 110 up or down.

The forearm extension 110 includes a body 140 having a first femalecoupling 142 located on a first end and a second female coupling 144located on a second end. The first female coupling 142 is for attachmentto the shaft 114 of the second end cap 108. The second female coupling144 is for attachment to a device mounting (not shown) such as a tilter,as described in Applicant's co-pending patent application No. 60/137,088filed on Jun. 2, 1999; a platform or other means for supporting aflat-screen device.

Additional advantages and features of the individual components,according to various embodiments of the present invention, are furtherdescribed below.

End Caps 102, 108

FIG. 9(a) illustrates a side view, and FIG. 9(b) illustrates a top viewof the first end cap 102 and the second end cap 108, in accordance withone embodiment of the invention. In the embodiment shown, each of thefirst and second end caps 102, 108 includes the partially-enclosedhousing 112 which has flat, oppositely-disposed endwalls 146 and 148fixedly connected by a sidewall 150. The sidewall 150 extends partiallyaround the partially-enclosed housing 112 so as to permit manipulationof components to be assembled within the first and second end caps 102,108. In one embodiment, the endwalls 146 and 148 are semicircular inshape and are connected along a semi-circular edge to the sidewall 150,which extends perpendicularly therebetween.

FIG. 9(a) is a side view (from the perspective of the open region of thesidewall 150), that illustrates the first and the second end caps 102,108 having the shaft 114 disposed on the endwall 148. The shaft 114 ispreferably integrally molded to the endwall 148 of each of the end caps102, 108. Preferably the entire end caps 102, 108 (partially enclosedhousings 112 and shafts 114) are molded from zinc. The endwall 146 has ahole 152 disposed therethrough. Within the partially enclosed housing112 and integrally molded on the sidewall 150 adjacent the endwalls 146,148 are stops 156. The stops 156 serve to stop upward or downwardmovement of the extension arm 100 when ends of the lower channel 106 andthe upper channel 104, respectively, meet the stops 156 when theextension arm 100 is in extended positions.

Also within the partially-enclosed housing 112, and integrally molded tothe inner surface of the sidewall 150 are trough walls 158 which runlongitudinally along the inner surface of the sidewall 150 between theendwalls 146 and 148 so as to define a trough 160 therebetween. FIG.9(b) illustrates a side view of the trough 160 disposed between thetrough walls 158.

Additionally within the partially enclosed housing 112 and integrallymolded with the inner surface of the sidewall 150, and proximate theendwall 148, are shelves 162. FIG. 9(b) illustrates a side view of theshelves 162 which define co-planar faces separated by a groove 164. Theshelves 162 have a connection means, such as self-tapping screw holes154 disposed therein. The co-planar faces of the shelves 162 areconfigured to engage the retainer clip 126, which is fastened in placeby, for example, the pair of screws 128. When the retainer clip 126 isfastened in place, the groove 164 defines a spacing for accepting oneend of the threaded rod 124, as discussed below.

The first end cap 102 and the second end cap 108 are identical at thispoint. However, while the manufacturing of the second end cap 108 iscomplete, the first end cap 102 still requires assembly of the threadedrod 124 and the clevis 120. The threaded rod 124 is employed within thefirst end cap 102 so as to adjustably support the clevis 120. FIG. 9(c)illustrates the threaded rod 124 in greater detail. A first end 166 hasa circular cross-section within which is axially disposed a shapedopening 168, for example a hex-shaped opening, for accepting a shapedkey (not shown), such as a hex-shaped key. Advantageously, across-sectional diameter of the first end 166 is smaller than across-sectional diameter of the hole 152, so as to be inserted therein.Adjacent the first end 166 is a shoulder 170. Advantageously, theshoulder 170 has a circular cross-section having a diameter that islarger than the cross-sectional diameter of the hole 152. Thus, in thepreferred embodiment, the shoulder 170 abuts an inner surface of theendwall 146 and retains the first end 166 within the hole 152.

The threaded rod 124 also includes a threaded section 172 which isconfigured to threadingly engage the clevis 120. The second end 174 ofthe threaded rod 124 is disposed in the groove 164 located between theshelves 162 of the first end cap 102. Preferably, the second end 174 ofthe threaded rod 124 has a circular cross-section having a diameter thatis smaller than the size of the groove 164, such that the second end 174is supported between the shelves 162 but is free to rotate therein.

As previously mentioned, threadedly mounted on the threaded rod 124 isthe clevis 120. The clevis 120 as illustrated in FIG. 9(d), has a tappedhole 176 formed therein for receiving the threaded rod 124. The clevis120 also has a fastening member 178 at a first end, which is fastened toone end of the gas spring 122. The second end of the clevis 120 isconfigured to slidably engage the trough 160.

When the first end 166 of the threaded rod 124 is engaged by the shapedkey, the shaped key is employed so as to rotate the threaded rod 124around its axial centerline. When the threaded rod 124 is rotated aroundthis axis of rotation, the clevis 120 moves along the length of thethreaded rod 124 in a direction that corresponds to the direction whichthe hex-shaped key is turned. This movement of the clevis 120 permitsthe gas spring 122 to be adjusted.

The end caps 102, 108 have numerous manufacturing advantages over theend caps 12, 18 of the prior art, and others like it. Unlike the priorart end caps 12, 18 which are different from each other, the end caps102, 108 are advantageously manufactured the same way. The threaded rodassembly 124 and the clevis 120 of the first end cap 102 aresubsequently assembled in the first end cap 102. Thus, the cost ofmanufacturing two different kinds of end caps are eliminated.

Moreover, the cost of manufacturing each end cap 102, 108 is reducedsignificantly. In the prior art, a significant part of the cost of thefirst end cap 12 is the steel shaft 22, which is machined separately,and then is inserted into the aluminum cast mold. By contrast, the shaft114 is integrally molded with the end caps 102, 108 by employinginterlocking mold technology. Interlocking molds permit a near-perfectmold to be made, minimizing the˜machining that is required to insurethat the shaft 114 is not out-of-round. By minimizing the amount ofmachining that is required to be performed on the shaft 114, the use ofinterlocking molds insures that the strength of the casting, which isprimarily located in the skin of the cast, is maximized.

As previously mentioned, all the components of the end caps 102, 108 arepreferably cast molded from zinc, though the present invention is notlimited in scope in this respect. Using zinc for the partially enclosedhousings 112 is an improvement over the aluminum end caps 12, 18employed in the prior art. That is, the zinc is stronger and moreflexible than the aluminum.

The first end cap 102 also has numerous assembly advantages over thefirst end cap 12 of the prior art, and others like it. For instance, theassembly time required to rotatably fasten the threaded rod 124 in thefirst end cap 102 is greatly reduced. In order to assemble the threadedrod 124 of the present invention, the first end 166 is inserted into thehole 152 until the shoulder 170 abuts the inner surface of the endwall146. The second end 174 of the threaded rod 124 is then positioned inthe groove 164 between the shelves 162. The second end 174 is held inplace by the retainer clip 126 which is fastened in place by, forexample, the screws 128, which are easily accessible due to theirproximity above the threaded rod 124. The first end 166 of the threadedrod 124 is perfectly aligned with the hole 152, and will remain so,because it is inserted for rotation therein.

By contrast, the assembly of the threaded rod 38 in the first end cap 12of the prior art is more complicated, and therefore, more costly. Forexample, the first end 40 is inserted into the hole 32 in the base ofthe end cap shaft 22. Next, the clevis 48 is mounted on the rod 38, andthen the second end 42 is fastened inside the first end cap 12 by theclip 44. The clip 44 is also employed to align the second end 42relative to the hole 36. Thus, the clip 44 must be fastened inside thefirst end cap 12 with precision, so as to insure that the second end 42is aligned relative to the hole 36 such that the second end 42 can beengaged by a hex-shaped key which is inserted into the hole 36.Moreover, the screws 46 which are employed to the fasten clip 44 insidethe first end cap 12 are difficult to access due to their positionunderneath the rod 38, thus complicating the process of aligning thesecond end 42 with the hole 36. In addition, the fastening of the clip44 inside the first end cap 12 is also rendered more difficult becausethe clevis 48 is already attached to the gas spring 28.

Unlike the prior art, the current invention does not require a forearmextension pin 92 to connect the second end cap 18 to the forearmextension 20. Moreover, the pin 96 is not required to hold the forearmextension pin 92 within the second end cap 18. Instead, the currentinvention uses the shaft 114 of the second end cap 108 to connect thesecond end cap 108 to the forearm extension 110. Thus, manufacturingcosts can be reduced since there in no need to manufacture the forearmextension pin 92 or the pin 96, and there is no reason to form the hole94 within the second end cap 18 or the hole 98 within the forearmextension pin 92 to accept the pin 96.

Upper Channel 104

FIGS. 10 a-d illustrate several views of the upper channel 104,according to one embodiment of the invention. The U-shaped body 130 ofthe upper channel 104 comprises a channel bottom 180 from which extendtwo channel sidewalls 182. Unlike the upper channel 14 of the prior artextension arm shown in FIGS. 4 a-b, which is stamped from heavy gaugesteel, the channel bottom 180 and the sidewall-S 182 of the upperchannel 104 are preferably integrally cast from zinc, which gives theupper channel 104 a lesser weight, and a degree of structural rigidity,more suitable for lighter-weight flat screen devices. At each end of thechannel bottom 180 are the rollers 132, which are also integrally cast.The rollers 132 have a hole 184 therethrough (either cast orsubsequently drilled) for receiving a connection mechanism, such as thepins 118. Additionally, the upper channel 104 comprises a threaded hole186 configured and sized to receive a threaded end of the ball stud 138.The threaded hole 186 is also integrally cast. The ball stud 138 isconfigured and sized to receive one end of the gas spring 122.

The upper channel 104 has numerous manufacturing advantages over theupper channel 14 of the prior art, and others like it. For instance,with reference to the upper channel 14 of the prior art shown in FIGS. 4a-b, the welding which is required to attach the rollers 66 to the upperchannel 14 is difficult to perform. The axial centerlines of the rollers66 must be near-perfectly parallel to each other, while beingnear-perfectly perpendicular to the longitudinal centerline 76 of thechannel bottom 60. The tolerances for these angles are very small so asto insure that the lower channel 16 engages the upper channel 14 whenthe parallelogram is adjusted. These tolerances are very difficult tomeet when the rollers 66 are welded to the upper channel 14. Bycontrast, the rollers 132 of the upper channel 104 of the presentinvention are integrally cast so as to insure that the axial centerlinesof rollers 132 are simultaneously perfectly parallel to each other andperfectly perpendicular to a longitudinal centerline 188 of the channelbottom 180.

Additionally, with further reference to FIGS. 4 a-b and as previouslynoted, due to the hardness of the steel employed for the prior art upperchannel 14, the rollers 66 must be MIG welded thereto, which in turnrequires the rollers 66 to be fabricated from expensive cold-rolledsteel. Although it is tempting for a manufacturer of the rollers 66 toemploy a cheaper material, such as leadloy, these cheaper materials donot provide a safe and consistent weld when joined to the steel upperchannel 14. Typically, tests must be performed on the roller material toinsure that leadloy has not been supplied. By contrast, the upperchannel 104 of the present invention requires no welding, eliminatingthe cost. of aligning the rollers, the cost of performing the weldingand the cost of testing the rollers to determine if they are a suitablewelding material.

In additional disadvantage of welding the rollers 66 to the upperchannel 14 is that the heat produced by welding the rollers 66 to theupper channel 14 may cause the upper channel 14 to curl or deform. Ifthis occurs, alignment of the rollers 66 is ruined and the upper channel14 is rendered useless, requiring it to be discarded. By eliminating anywelding required during the manufacture of the upper channel 104, thelikelihood of heat-deforming the upper channel 2-04 is also eliminatedand materials are not wasted.

As previously mentioned, the prior art upper channel 14 is made ofsteel, which means that the upper channel 14 is formed by heating apiece of steel and bending the steel to form the channel bottom 60 aridthe sidewalls 62. Thus, precise manufacturing is required to ensure thesidewalls 62 extend up from the channel bottom 60 at 90 degree angles.If the angle is slightly off it will likely cause the upper channel 14and the lower channel 16 to scrape against one another. The use of castmolding in the current invention ensures the angle between the channelbottom 180 and the sidewalls 182 is exactly the same each and everytime. Thus, the likelihood of scraping is greatly reduced, if noteliminated.

Moreover, as illustrated in FIGS. 10 c and 10 d, which arecross-sectional views of the upper channel 104, the sidewalls 182 aretapered. Both an outer surface and an inner surface of the sidewalls 180tapers in approximately 1 degree. The taper is possible because theupper channel 104 is, in the preferred embodiment, cast molded. Thetaper provides several advantages including more clearance between theupper and the lower channels 104, 106 when the upper and the lowerchannels 104, 106 are brought together during usage. That is, the innersurface of the sidewall 180 being displaced by 1 degree means that therewill be additional clearance for the lower channel 106 to fittherewithin. The additional clearance will help prevent the upperchannel 104 and the lower channel 106 from scraping together. Thus,damage to the paint or other coating that may cover the upper and thelower channels 104, 106 will be further reduced, if not eliminated.Moreover, less material is needed at outer edges of the sidewalls 182.Furthermore, the taper is more aesthetically pleasing to the eye of theuser.

Additionally, the upper channel 104 eliminates the requirement for thestiffener 70, which, with reference to FIGS. 4 a-b, is welded to theinner surface of the channel bottom 60 in the upper channel 14 of theprior art. Unlike the upper channel 14 of the prior art, the upperchannel 104 does not require the additional structural rigidity providedby the stiffener 70. By eliminating the stiffener 70, the upper channel104 of the present invention also saves the steps required to weld thestiffener 70 to the channel bottom 60 which are required by the priorart upper channel 14.

Moreover, additional assembly steps are saved by integrally casting thethreaded hole 186 in the upper channel 104 of the current invention. Forinstance, the prior art upper channel 14 has the threaded ball stud 72penetrate a hole disposed in the stiffener 70 and is fixed in place bythe nut 74. In order to install the bail˜1 stud 72, it is required thatthe threaded end of ball, stud 72 be inserted through the hole in thestiffener 70 and be fixed in place by the nut 74 prior to the stiffener70 being welded in place. No such assembly is required with the upperchannel 104 of the present invention.

An additional problem experienced by prior art upper channels 14 is theneed to mask openings, such as the holes 68 in the rollers 66 thatreceive the pins 28 therethrough, when the upper channel is painted orotherwise coated. Specifically, labor is required in order to insertmasking material into the openings and then to remove the maskingmaterial after the paint has been applied. By contrast, the openings ofthe present invention are according to one embodiment, precision-drilledafter an application of paint or other coatings, thus eliminating theexpense of masking any openings.

Lower Channel 106

FIGS. 11 a-e illustrate several views of the lower channel 106,according to one embodiment of the invention. The U-shaped body 134 ofthe lower channel 106 comprises a channel bottom 190 from which extendtwo channel side walls 192. Unlike the lower channel 16 of the prior artextension arm shown in FIGS. 5 a-b, which is stamped from heavy gaugesteel, the channel bottom 190 and sidewalls 192 of the lower channel 106are preferably integrally cast from zinc, which gives the lower channel106 a lesser weight when compared to heavy gauge steel, and a degree ofstructural rigidity, more suitable for lighter-weight flat screendevices. At each end of the channel bottom 180 are the rollers 136,which are also integrally cast. The rollers 136 have a hole 194therethrough (either cast or subsequently drilled) for receiving aconnection mechanism, such as the pins 118. The channel bottom 190additionally includes a cable channel aperture 196 runninglongitudinally. In the embodiment shown, the cable channel aperture 196has rounded ends, which improves the rigidity of the lower channel 106.The cable channel aperture 196 is configured to receive a cable cover198 (illustrated in FIG. 11 e). The cable cover 198 is configured toremovably fit within the cable channel aperture 196. Thus, cables of themounted device may be substantially retained within the lower channel106 so as to hide them from view and protect them from harm. The cablechannel aperture 196 and the cable cover 198 enable cables to beaccessed when desired, while securing them within the lower channel 106.

The lower channel 106 has numerous manufacturing advantages over thelower channel 16 of the prior art, and other like it. For instance, asdescribed above with reference to the upper channel 104, the rollers 136of the lower channel 106 of the present invention are integrally cast soas to insure that the axial centerlines of the rollers 136 are perfectlyparallel to each other, and that the axial centerlines of the rollers136 are perfectly perpendicular to a longitudinal centerline 200 of thechannel bottom 2-90. Thus, the need for precision alignment of therollers 84 prior to welding to the lower channel 16 is eliminated.

Additionally, and as also described with reference to the upper channel104, the rollers 136 of the lower channel 106 are integrally cast so nowelding is required. Thus, the cost of performing the welding and thecost of testing the rollers to determine if they are a suitable weldingmaterial is eliminated. Another advantage of eliminating the need forwelding the rollers 136 to the lower channel 106 is reducing thelikelihood of heat-deforming the lower channel 106 so that materials arenot wasted.

As shown in FIGS. 11 c and 11 d, which are cross-sectional views of thelower channel 106, the sidewalls 192 of the lower channel 106 aretapered. An outer surface of the sidewalls 192 is tappered approximately{fraction (1/2)} degree while an inner surface is tappered approximately1 degree. The taper is possible because the lower channel 106 is, in thepreferred embodiment, cast molded. As rioted above with respect to theupper channel 104, the taper provides more clearance between the upperchannel 104 and the lower channel 106 so as to reduce or eliminate thechance of the upper and the lower channels 104, 106 scraping. Moreover,less material is needed at outer edges of the sidewalls 192. A furtheradvantage, as noted above with respect to the upper channel 104, is thatthe hole 194 within the rollers 136, according to one embodiment, isprecision-drilled after an application of paint or other coatings, thuseliminating the expense of masking any openings.

As illustrated in FIG. 11 e, the cable cover 198 includes a top cover202 with two sidewalls 204 pertruding therefrom. A far end of eachsidewall 204 has a catch 206 formed thereon so as to engage with thecable channel aperature 196.

Forearm Extension 110

With reference to FIGS. 12 a, 12 b, 13 a and 13 b, the forearm extension110 includes a body 140, which is preferably U-shaped so that a cablecan be hidden therein, having female couplings 142, 144 disposed at eachend. The V-shaped body 140 includes a topwall 207 and two side walls208. The female coupling 142 has an inner diameter 209 that is sized torotatably engage the shaft 114 of the second end cap 108. As illustratedin FIG. 8, the forearm extension 110 and the shaft 114 are securelyfastened to each other by connecting a screw 211 through a coupling top213 into a hole 215 (FIG. 9 a) within the shaft 114.

A bushing 210 (FIG. 8) is preferably used to engage the female coupling142 and the shaft 114. That is, the bushing 210 is placed over the shaft114 and within the female coupling 142. The bushing 210 is preferablymade of a smooth material, such as plastic, in order to reduce frictionand prevent metal to metal contact. The female coupling 142 preferablyhas a set screw 212 formed within a wall 214 of the female coupling 142.The set screw 212 is aligned to press against the bushing 210 atapproximately the location of a ridge 216 (see FIG. 9 a) on the shaft114 of the second end cap 108. When the set screw 212 is tightened itcauses the bushing 210 to flex inward and frictionally engage the shaft114 and thus prevent the forearm extension 110 from rotating about theshaft 114. Advantageously, the female coupling 142 has a plurality ofvoids 217 formed in the wall 214, which saves on material costs andpermits the forearm extension 2-10, when cast, to be cooled morequickly. The quicker cooling enables the production quantity to beincreased.

The female coupling 144 has an inner diameter 218 that is sized torotatably engage a shaft of a device mount, such as a tilter, platformor other device used to secure flat-screen devices. A bushing 220 (FIG.8), preferably made of a smooth material such as plastic, is placed overthe shaft and within the female coupling 144. The female coupling 144preferably has a set screw 222 formed within a wall 224 of the femalecoupling 144. When the set screw 222 is tightened it. causes the bushing220 to flex inward and frictionally engage the shaft and thus preventthe device mount from rotating around the female coupling 144.Advantageously, the female coupling 144 also has a plurality of voids226 formed in the wall 224.

FIGS. 12 a and 2˜2 b illustrate one embodiment of the forearm extension110, wherein the center of the female couplings 142, 144 are alignedwith a longitudinal centerline 228 of the body 140. As illustrated inFIG. 12 b, when the axial centerlines of the female couplings 142, 144are vertically disposed, the body 140 inclines at an angle, such as a 15degree angle as specifically illustrated in FIG. 12 b. It should benoted however that the incline angle is not limited to 15 degrees, and.there may in fact be no incline at all in this embodiment.

FIGS. 13 a and 13 b illustrate another embodiment of the forearmextension 110, wherein the center of the female couplings 142, 144 donot align with the axial centerline 228 of the body 140. Rather the body140 is flush with an upper edge of the female coupling 142, resulting inthe center of the female coupling 142 being offset from the center ofthe female coupling 144. As illustrated in FIG. 13 b, when the axialcenterlines of the female couplings 142, 144 are vertically disposed,the body 140 is horizontally disposed therebetween. It should be notedhowever that the body 140 is not limited to be horizontally disposed andmay be disposed at an incline in this embodiment.

Extension Arm 100

In addition to improvements in manufacturing and assembly, the presentinvention also offers a functional interchangeability which is notpresent in the prior art. For instance, several forearm extensions 110and/or extension arms 100 can be connected end-to-end to provideadditional extension length or additional adjustability.

A dual purpose of flat-screen devices is to minimize the amount of spacewhich they occupy while simultaneously being aesthetically pleasing tothe eye. Thus, it is desirable that an extension arm for a flat-screendevice be able to be mounted substantially flat to its mounting surfacewhile hiding the extension arm behind it. The present invention permitsa flat-screen device which is mounted to a wall to be flattened againstthe wall while hiding the extension arm 100 within the shadow of thedevice.

The prior art extension arms 10 did not allow this functionality.Referring to FIG. 1, if a wall is defined by the plane of the page, itcan be seen that a device inserted into the hole 26 may be substantiallyflattened against the wall when the upper and the lower channels 14, 16and the forearm extension 20 are flush against the wall. A flat-screencomputer monitor, which is typically about 15 inches wide, will hidefrom view the forearm extension 20, but may leave exposed theparallelogram formed by the first end cap 12, the upper channel 14, thelower channel 16 and the second end cap 18. In order to hide theparallelogram, the forearm extension 20 needs to be rotated about theforearm extension pin 92 toward the first end cap 12. However, the upperand the lower channels 14, 16 and the first end cap 12 will prevent theforearm extension 20 from being flush against the wall in thisconfiguration. Thus, it is clear that the prior art extension arms 10could only provide the ability to mount a device˜flush to the wall orthe ability to mount a device so as to hide the forearm extension 20,but not both.

By contrast, the upper and the lower channels 104, 106 of the presentinvention do not interfere with the rotation of the forearm extension110. That is, the forearm extension 110 may be folded into a positionwhich is directly above the upper and the lower channels 104, 106. As aresult, the mounted device is flush to the mounting surface andsubstantially hides the parallelogram, formed by the first and thesecond end caps 102, 108 and. the upper and the lower channels 104, 106,as well as the forearm extension 110 from view. Thus, the aestheticappeal of the extension arm 100 is increased and the space occupied bythe extension arm 100 and the device is minimized.

While only certain features of the invention have been illustrated anddescribed herein, many modifications, substitutions, changes orequivalents will now occur to those skilled in the art. It is therefore,to be understood that the appended claims are intended to cover all suchmodifications and changes that fall within the true spirit of theinvention.

1. A method of forming by integral casting an extension arm thatadjustably mounts a device to a support, said method comprisingintegrally casting as one piece an upper channel having integrally casttherewith rollers at each end thereof; integrally casting as one piece alower channel having integrally cast therewith rollers at each endthereof; integrally casting as one piece a first end cap; providing aclevis having a fastening member; integrally casting as one piece asecond end cap; integrally casting as one piece a forearm extensionhaving a body, a first end for connecting to the second end cap and asecond end adapted for connecting to the device; connecting one end of agas spring to the upper channel and a second end of the gas spring tothe fastening member of the clevis; attaching the upper channel, thelower channel, the first end cap and the second end cap to form aparallelogram; and connecting the first end of the forearm extension tothe second end cap.
 2. The method of claim 1, wherein said first andsecond end caps are substantially identical.
 3. The method of claim 1,wherein said integrally casting said second end cap includes casting apartially enclosed housing having a first endwall, a second endwall andat least one sidewall.
 4. The method of claim 3, further includingforming a shaft connected to said second endwall.
 5. The method of claim1, wherein said integrally casting said first end cap includes casting apartially enclosed housing having a first endwall, a second endwall andat least one sidewall.
 6. The method of claim 5, further includingforming a shaft connected to said first endwall.
 7. A method of formingby integrally casting an extension arm that adjustably mounts a deviceto a support, said method comprising integrally casting as one piece anupper channel including a U-shaped body having integrally cast therewitha roller at each end thereof, said U-shaped body having a bottom wallformed with a hole contained therein; integrally casting as one piece alower channel including a U-shaped body having integrally cast therewitha roller at each end thereof; integrally casting as one piece a firstend cap; providing a first shaft connected to said first end cap;providing a clevis having a fastening member; integrally casting as onepiece a second end cap; providing a second shaft connected to saidsecond cap; integrally casting as one piece a forearm extension having abody and a shaft coupling for connecting to the second end cap; mountinga ball stud in the hole of the upper channel; connecting one end of agas spring to the ball stud and a second end of the gas spring to thefastening member of the clevis; attaching the upper channel, the lowerchannel, the first end cap and the second end cap to form aparallelogram; and connecting the shaft coupling of the forearmextension to the second end cap.
 8. The method of claim 7, wherein saidintegrally casting as one piece said forearm extension comprises castingsaid forearm extension having a U-shaped body.
 9. The method of claim 7,wherein said first and second end caps are identical.
 10. The method ofclaim 7, wherein said integrally casting as one piece said second endcap includes casting a partially enclosed housing having a firstendwall, a second endwall and at least one sidewall.
 11. The method ofclaim 7, wherein said integrally casting said first end cap includescasting a partially enclosed housing having a first endwall, a secondendwall and at least one sidewall.
 12. The method of claim 7, furtherincluding attached a device mounting assembly to said forearm extension.13. The method of claim 12, further including coupling an electronicdevice to said device mounting assembly.
 14. The method of claim 13,wherein said electronic device comprises a flat screen display.